This section of the scientific article provides an in-depth analysis of the mechanisms underlying antibiotic resistance as a complex biological and genetic process that enables microorganisms to survive under antimicrobial pressure. Antibiotic resistance is considered an adaptive response driven by selective pressure, resulting in the emergence and spread of resistant bacterial strains.

The study examines key molecular mechanisms of resistance, including genetic mutations that alter antibiotic target sites, thereby reducing drug effectiveness. It also highlights the role of horizontal gene transfer, involving plasmids, transposons, and bacteriophages, which facilitates the rapid dissemination of resistance genes among bacterial populations.

Particular emphasis is placed on enzymatic inactivation of antibiotics, especially through the production of beta-lactamases that degrade antibiotic molecules and render them ineffective. Additionally, the article discusses mechanisms that reduce membrane permeability, limiting antibiotic entry into the bacterial cell, as well as efflux pump systems that actively expel antibiotics, lowering their intracellular concentration.

Furthermore, structural modifications of target sites, such as ribosomes and enzymes, are analyzed as critical factors that prevent effective antibiotic binding. These combined mechanisms illustrate the multifaceted nature of antibiotic resistance and underscore its significance as a major challenge in modern medicine.

antibiotic resistance, bacteria, genetic mutations, horizontal gene transfer, plasmids, beta-lactamases, efflux pumps, membrane permeability, microbiology, pathophysiology

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